KR20010039507A - Metallocenes for multimetallic polymerization catalysts - Google Patents

Abstract

The present invention relates to novel metallocene compounds comprising two or more transition metals.

Description

Metallocene for multimetal polymerization catalysts {METALLOCENES FOR MULTIMETALLIC POLYMERIZATION CATALYSTS}

Catalysts containing two or more transition metals have been synthesized. These catalysts have been used in olefin polymerization reactions such as ethylene polymerization reactions and copolymerization reactions. Recently, reports have reported catalysts synthesized to include two or more transition metals in the form of metallocenes or in the form of combinations of metallocenes and Chiegler-Natta catalysts. Early catalysts comprising two transition metals were prepared as physical mixtures supported or not supported on a carrier. Interaction between two different transition metal sources in a single catalyst can affect the final activity and selectivity of the two transition metals.

The present invention relates to novel metallocene compounds comprising at least two transition metals.

The present invention relates to a composition defined by formula (I)

(ML) _r B

Wherein M is a transition metal moiety and L is each a linking group, each of which L may be the same or different, as described below, and an atomic moiety or molecule defined generally as B and a transition metal moiety The moieties are linked through the linking group L to form star molecules. The subscript r is a number not exceeding the number of valence electrons of B. Molecules containing two or more transition metals can be used as the catalyst composition. The transition metal containing molecule may polymerize ethylene or copolymerize ethylene with a second αolefin. When using the composition as a catalyst for the olefin polymerization reaction, the composition can be used alone or as an alumoxane and / or monomeric Al (III) compound (e.g. trialkylaluminum or dialkylaluminum halide or hydride, these Alkyl in the compound is methyl, ethyl, butyl, isobutyl, respectively) and / or ionic Lewis acid activator (eg, B (C ₆ F ₆ ) ₃ , [Ph ₃ C] ⁺ [B (C ₆ F ₅ ) ₄ ]).

In such polyolefin catalysts for olefin polymerization or olefin copolymerization reactions comprising two or more different catalyst sites, each site is characterized by the characteristic type of polymer (ie, molecular weight, molecular weight distribution, short chain branching by comonomer incorporation, Long chain branching and the like). When two or more of these sites are bound to a single catalyst molecule, polymer products exhibiting various types of molecular weights, branching and other properties can be prepared and prepared using a single catalyst molecule, thus making these different polymer molecules. Thorough blending of these at the molecular level improves the physical properties of the blended polymer product.

More specifically, the present invention relates to a composition characterized by the following formula (II):

(M ¹ _a L ¹ _b ) _x (M ² _c L ² _d ) _y (M ³ _e L ³ _f ) _z W (M ⁴ _g L ⁴ _h ) _m

Wherein W is silicon, boron, carbon or nitrogen and derivatives thereof,

x, y, z and m are less than the number of valence electrons in W, m + x + y + z is equal to the number of valence electrons in W,

M ¹ , M ² , M ³ and M ⁴ are the same or different, respectively, MeX ¹ X ² X ³ , wherein Me is a transition metal of Group IV or Group V of the periodic table, preferably hafnium, zirconium or titanium, X ¹ , X ² and X ³ may be the same or different, each having a halide (iodide, bromide, chloride or fluoride), alkyl having 1 to 6 carbon atoms, Cp wherein Cp is an unsubstituted cyclo Pentadienyl, one or more straight or branched chain alkyls having 1 to 6 carbon atoms or cyclopentadienyl substituted with saturated or unsaturated alkylenes having 1 to 8 carbon atoms (these are bicyclic or tricyclic derivatives (eg, Forming a substituted or unsubstituted indenyl or fluorenyl)] or an amide [eg, NR'R "wherein R 'and R" are alkyl or aryl),

L ¹ , L ² , L ³ and L ⁴ are each unsubstituted cyclopentadienyl, cyclo substituted with alkyl having 1 to 6 carbon atoms (eg methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc.) Pentadienyl, alkyl having 1 to 6 carbon atoms or alkylene having 1 to 6 carbon atoms (e.g. methylene), 6 to 18 carbon atoms, unsubstituted aryl (phenyl or benzyl) or F, carbon atoms 1-10 alkyl, diynyl (-C≡C-C≡C-) _n (wherein n is 1-4), aryl (phenyl or benzyl) substituted by alkylsilyl group or alkylene group,

b, d, f and h are each 0, 1 or 2,

a, c, e and g are each 0 or 1, but a + c + e + g = 2 or more.

W is silicon, boron, nitrogen or carbon and is a compound including organic derivatives thereof.

The composition of the present invention can be used alone or in combination with a support as a catalyst. Thus, unsupported catalysts and supported catalysts can be prepared in the present invention. Supports or carriers are used interchangeably herein and are preferably selected from the group consisting of silica, alumina or silica / alumina. In a preferred embodiment, the silica has OH (hydroxyl) groups. As a result of the presence of the hydroxy component, the compound may be bound to the carrier via reaction or bonding of W to the surface hydroxyl group. The composition can be used as a catalyst with or without an activator.

The composition of the present invention can be synthesized according to various methods, wherein at least two of the groups comprising L ¹ , L ² , L ³ and L ⁴ are substituted or unsubstituted cyclopentadienyl, prepared as follows. can do. An unsubstituted cyclopentadiene or substituted derivative thereof containing an acidic hydrogen atom on its ring is contacted with sodium or butyl lithium to form an alkali metal salt of a substituted or unsubstituted cyclopentadiene. Forming the alkali metal salt may be carried out at a temperature of -78 ° C to + 30 ° C in a suitable solvent such as ether or hydrocarbon solvent. This salt can be separated. Thereafter, the alkali metal salt and trichloromethylsilane (MeSiCl ₃ ) are reacted at a molar ratio of 3 moles or more of alkali metal salts: 1 mole of silane to give a triscyclopentadienyl compound such as tris (cyclopentadienyl) methylsilane. Can be formed. The protons are then removed by reacting a silane compound in which the precursor chloro group (of trichloromethylsilane) is substituted with a cyclopentadienyl group with a suitable base such as 1 equivalent, 2 equivalents, 3 equivalents or more equivalents, followed by 1 Contact with at least two species of transition metal salts. The transition metal salt may be a halide (chlorine, or bromine, for example TiCl ₄ or ZrCl ₄ ). Alternatively, the transition metal salt may be an alkyl transition metal salt or halide containing one or more cyclopentadienyl groups unsubstituted or substituted with alkyl groups having 1 to 6 carbon atoms or alkylene groups having 1 to 6 carbon atoms. have. The desired compound is separated by recrystallization, sublimation or other suitable means. The transition metal of the transition metal salt may be zirconium, hafnium or titanium, and mixtures thereof. When X ¹ , X ² or X ³ of MeX ¹ X ² X ³ is cyclopentadienyl, the cyclopentadienyl may be an unsubstituted, monosubstituted or polysubstituted cyclopentadienyl group. Cyclopentadienyl substituent of the carbonyl vapor is preferably a straight or branched chain C ₁ -C ₆ alkyl group. The cyclopentadienyl group may be a bicyclic or tricyclic moiety such as indenyl, tetrahydroindenyl, fluorenyl or part of a partially hydrogenated fluorenyl group and may be substituted bicyclic or tricyclic It may be part of a portion, and X ¹ , X ² and X ³ may each be the same or different. Further, the cyclopentadienyl groups are polymethylene group or a dialkyl silane groups, such as _{-CH 2 -, -CH 2 -CH 2} -, -CR'R "- and -CR'R"-CR'R"- Wherein R 'and R "are short-chain alkyl groups or hydrogen atoms, -Si (CH ₃ ) _2- , -Si (CH ₃ ) ₂ -CH ₂ -CH ₂ -Si (CH ₃ ) ₂ -and similar It can be connected by a coupler. The alkyl group is preferably a straight or branched C ₁ -C ₈ alkyl group, for example methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, n-hexyl or n-octyl. Suitable cyclopentadienyl groups include indenylcyclopentadienyl, pentamethylcyclopentadienyl, n-butylcyclopentadienyl, isobutylcyclopentadienyl, dimethylcyclopentadienyl, indenyl, 4,5,6 , 7-tetrahydro-1-indenyl and ethylene- (bis (4,5,6,7-tetrahydro-1-indenyl)).

(M ¹ _a L ¹ _b ) _x (M ² _c L ² _d ) _y (M ³ _e L ³ _f ) _z W (M ⁴ _g L ⁴ _h ) _m produced in the presence of a composition containing or derived therefrom Ethylene resins, homopolymers or copolymers contain residues of the composition. It contains 0.01 ppm to 4500 ppm of transition metal (provided as M ¹ , M ² , M ³ and M ⁴ ). The ethylene copolymer contains as comonomer at least one olefin having 3 to 10 carbon atoms, preferably 1-butene, 1-hexene or 1-octene.

The olefin polymerization reaction can be carried out in solution, in slurry or in gas phase. When ethylene polymerization or copolymerization of ethylene with α-olefins having 3 to 10 carbon atoms is carried out in the gas phase, for example in a fluidized bed, it is essential to operate the fluidized bed reactor at temperatures below the sintering temperature of the polymer particles. to be. In order to ensure that sintering does not occur, it is necessary to use an operating temperature which is below the sintering temperature. In order to produce ethylene copolymers in the process of the invention, it is preferred that the operating temperature is from 60 ° C to 115 ° C, most preferably from 75 ° C to 95 ° C.

Fluidized bed reactors operate under pressures of about 150 psig to 350 psig, and it is good in terms of heat transfer to operate at pressures higher than this range, as the pressure increases and the gas unit volume heat capacity increases.

"Diluent" gases can be used in the polymerization reaction. This gas is inert under the conditions in the polymerization reactor. The diluent gas can be nitrogen, argon, helium, methane, ethane and the like.

In a fluidized bed reactor, the surface gas velocity through which the gas phase reaction mixture passes through the bed must exceed the minimum flow rate required for fluidization and be at least 0.2 ft / sec above the minimum flow rate. Typically, the surface gas velocity does not exceed 5.0 ft / sec, most typically less than 2.5 ft / sec is sufficient. It supplies a feed stream composed of the gaseous monomer not containing or containing an inert diluent gas into the reactor bed volumes of 1 ft ³ operating under about 2-20 lbs / space-time yield at the time of each.

In the preparation of the film, the product may contain various additives which are usually added to the polymer composition, examples of such additives include lubricants, microtalcs, stabilizers, antioxidants, compatibilizers, pigments and the like. Reaction reagents may also be used to stabilize the product against oxidation. For example, using an additive package used to add to the resin powder, consisting of 400-1200 ppm sterile phenols, 700-2000 ppm phosphite, 250-1000 ppm antistatic agent and 250-1000 stearate Pellet can be formed. The polymer may be added to a blown film extruder, such as a Sterling extruder, to directly prepare a film having a thickness of about 0.5 to 5 mils.

Resin prepared using the multimetallic catalyst according to the present invention may be used for various other purposes, for example, blow molding, injection molding or rotational molding applications. By constructing the site of the multimetallic catalyst so as to be suitable for producing a polymer molecule having certain properties (e.g., molecular weight, molecular weight distribution, short chain branch from comonomer or long chain branch from comonomer, etc.) The type of resin produced by the catalyst can be adapted to the particular application. In this regard, the present invention provides significant advantages over conventional techniques.

Claims (4)

An ethylene homopolymer or copolymer of ethylene with at least one comonomer, comprising a moiety of a composition of formula II: Formula II (M ¹ _a L ¹ _b ) _x (M ² _c L ² _d ) _y (M ³ _e L ³ _f ) _z W (M ⁴ _g L ⁴ _h ) _m In the above formula, W is silicon, boron, carbon or nitrogen, x, y, z and m are less than the number of valence electrons in W, m + x + y + z is equal to the number of valence electrons in W, M ¹ , M ² , M ³ and M ⁴ are the same or different, respectively, MeX ¹ X ² X ³ , where Me is a transition metal, preferably hafnium, zirconium or titanium, and X ¹ , X ² and X ³ may each be the same or different, each halide, alkyl having 1 to 6 carbon atoms, or Cp [wherein Cp is unsubstituted cyclopentadienyl, at least one straight or branched chain having 1 to 6 carbon atoms Cyclopentadienyl substituted with chain alkyl or saturated or unsaturated alkylene having 1 to 8 carbon atoms, which form a bicyclic or tricyclic derivative of cyclopentadienyl; L ¹ , L ² , L ³ and L ⁴ are each unsubstituted cyclopentadienyl, cyclo substituted with one or more alkyls of 1 to 6 carbon atoms (methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc.) Pentadienyl, alkyl having 1 to 6 carbon atoms or alkylene having 1 to 6 carbon atoms (e.g. methylene), 6 to 18 carbon atoms, unsubstituted aryl (phenyl or benzyl) or F, carbon atoms 1-10 alkyl, diynyl (-C≡C-C≡C-) _n (wherein n is 1-4), aryl (phenyl or benzyl) substituted by alkylsilyl group or alkylene group, b, d, f and h are each 0, 1 or 2, a, c, e and g are each 0 or 1, but a + c + e + g = 2 or more. A process for preparing a polymer or copolymer of ethylene comprising contacting a feed comprising ethylene with a composition of formula II under ethylene polymerization conditions: Formula II (M ¹ _a L ¹ _b ) _x (M ² _c L ² _d ) _y (M ³ _e L ³ _f ) _z W (M ⁴ _g L ⁴ _h ) _m In the above formula, W is silicon, boron, carbon or nitrogen, x, y, z and m are less than the number of valence electrons in W, m + x + y + z is equal to the number of valence electrons in W, M ¹ , M ² , M ³ and M ⁴ are the same or different, respectively, MeX ¹ X ² X ³ , where Me is a transition metal, preferably hafnium, zirconium or titanium, and X ¹ , X ² and X ³ may each be the same or different, each halide, alkyl having 1 to 6 carbon atoms, or Cp [wherein Cp is unsubstituted cyclopentadienyl, at least one straight or branched chain having 1 to 6 carbon atoms Cyclopentadienyl substituted with chain alkyl or saturated or unsaturated alkylene having 1 to 8 carbon atoms, which form a bicyclic or tricyclic derivative of cyclopentadienyl; L ¹ , L ² , L ³ and L ⁴ are each unsubstituted cyclopentadienyl, cyclo substituted with one or more alkyls of 1 to 6 carbon atoms (methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc.) Pentadienyl, alkyl having 1 to 6 carbon atoms or alkylene having 1 to 6 carbon atoms (e.g. methylene), 6 to 18 carbon atoms, unsubstituted aryl (phenyl or benzyl) or F, carbon atoms 1-10 alkyl, diynyl (-C≡C-C≡C-) _n (wherein n is 1-4), aryl (phenyl or benzyl) substituted by alkylsilyl group or alkylene group, b, d, f and h are each 0, 1 or 2, a, c, e and g are each 0 or 1, but a + c + e + g = 2 or more. A product made by the method as defined in claim 2. A catalyst or catalyst precursor composition having the formula II: Formula II (M ¹ _a L ¹ _b ) _x (M ² _c L ² _d ) _y (M ³ _e L ³ _f ) _z W (M ⁴ _g L ⁴ _h ) _m In the above formula, W is silicon, boron, carbon or nitrogen, x, y, z and m are less than the number of valence electrons in W, m + x + y + z is equal to the number of valence electrons in W, M ¹ , M ² , M ³ and M ⁴ are the same or different, respectively, MeX ¹ X ² X ³ , where Me is a transition metal, preferably hafnium, zirconium or titanium, and X ¹ , X ² and X ³ may each be the same or different, each halide, alkyl having 1 to 6 carbon atoms, or Cp [wherein Cp is unsubstituted cyclopentadienyl, at least one straight or branched chain having 1 to 6 carbon atoms Cyclopentadienyl substituted with chain alkyl or saturated or unsaturated alkylene having 1 to 8 carbon atoms, which form a bicyclic or tricyclic derivative of cyclopentadienyl; L ¹ , L ² , L ³ and L ⁴ are each unsubstituted cyclopentadienyl, cyclo substituted with one or more alkyls of 1 to 6 carbon atoms (methyl, ethyl, propyl, isopropyl, butyl, isobutyl, etc.) Pentadienyl, alkyl having 1 to 6 carbon atoms or alkylene having 1 to 6 carbon atoms (e.g. methylene), 6 to 18 carbon atoms, unsubstituted aryl (phenyl or benzyl) or F, carbon atoms 1-10 alkyl, diynyl (-C≡C-C≡C-) _n (wherein n is 1-4), aryl (phenyl or benzyl) substituted by alkylsilyl group or alkylene group, b, d, f and h are each 0, 1 or 2, a, c, e and g are each 0 or 1, but a + c + e + g = 2 or more.